Cephalosporan derivatives and their preparation

ABSTRACT

Cis, trans and cis-trans mixtures of DL 7-R-amino-desacetoxycephalosporan compounds of the formula   wherein R is selected from the group consisting of hydrogen and trityl and R1 is selected from the group consisting of lower alkyl of 1 to 6 carbon atoms optionally substituted with at least one chlorine and aralkyl of 7 to 15 carbon atoms with the proviso when R is hydrogen, R1 is selected from the group consisting of tert.-butyl,benzyl and ethyl, processes for their preparation and novel intermediates produced therein.

United States Patent 1191 Martel et al.

[ Aug. 19, 1975 CEPHALOSPORAN DERIVATIVES AND THEIR PREPARATION [75]Inventors: Jacques Martel, Bondy; Rene Heymes, Romainville, both ofFrance [30] Foreign Application Priority Data Feb. 18, 1971 France71.05555 Feb. 18, 1971 France 71.05556 [52] U.S. Cl. 260/243 C; 424/246[51] Int. Cl C07d 99/24 [58] Field of Search 260/243 C [56 ReferencesCited UNITED STATES PATENTS 3,487,070 12/1969 Sheehan 260/239 3,546,21 I12/1970 Bose 1 260/239 3,708,477 1/1973 Martel 260/243 C OTHERPUBLICATIONS Blatt, ed., Organic Syntheses," Vol. 2, Wiley and Sons, NewYork, (1943), p. 15.

Primary Examinerl\1icho1as S. Rizzo Attorney, Agent, or FirmHammond &Littell 57 ABSTRACT Cis, trans and cis-trans mixtures of DL7-R-aminodesacetoxy-cephalosporan compounds of the formula wherein R isselected from the group consisting of hydrogen and trityl and R isselected from the group consisting of lower alkyl of l to 6 carbon atomsoptionally substituted with at least one chlorine and aralkyl of 7 to 15carbon atoms with the proviso when R is hydrogen, R, is selected fromthe group consisting of tert.-butyl,benzy1 and ethyl, processes fortheir preparation and novel intermediates produced therein.

4' Claims, No Drawings CEPIIALOSPORAN DERIVATIVES AND THEIR PREPARATIONOBJECTS OF THE INVENTION It is an object of the invention to provide thenovel DL 7-R amino-desacetoxy-cephalosporanic acid compounds of formulaI.

It is a further object of the invention to provide novel processes forproducing the compounds of formula I.

It is another object of the invention to provide novel intermediates forthe preparation of compounds of formula I.

These and other objects and advantages will become obvious from thefollowing detailed description.

THE INVENTION The novel products of the invention are selected from thegroup consisting of cis, trans and cis-trans mixtures of DL7-R-amino-desacetoxy-cephalosporanic compounds of the formula COORwherein R is selected from the group consisting of hydrogen and trityland R is selected from the group consisting of lower alkyl of 1 to 6carbon atoms optionally substituted with at least one chlorine andaralkyl of 7 to 15 carbon atoms with the proviso that when R ishydrogen, R is selected from the group consisting of tert.-butyl, benzyland ethyl.

Examples of specific compounds of formula I are the tert.-butyl ester ofDL 7-amino-desacetoxy-cephalosporanic acid and its 7-tritylaminoderivative, the benzyl ester of DL 7-amino-desacetoxy-cephalosporanicacid and its 7-tritylamino derivative and the ethyl ester of DL7-amino-desacetoxy-cephalosporanic acid and its 7-tritylaminoderivative.

The novel total synthesis process of the invention is directed tocompounds of the formula in the form of cis, trans or cis-trans mixtureswherein R is selected from the group consisting of hydrogen and trityland R is lower alkyl of l to 6 carbon atoms optionally substituted withat least one chlorine and aralkyl of 7 to 15 carbon atoms comprisesreacting an enamine of the formula Ill \COOR,

wherein R is selected from the group consisting of alkyl of l to 10carbon atoms and aralkyl of? to car- OOR:3

which occurs in erythro and/or threo isomeric form, reacting the latterin the presence of a tertiary amine with an ester ofa-keto-B-methylene-butyric acid of the formula wherein R has the abovedefinition to form a 1,3- thiazane of the formula HO cooR in the form ofits erythro and/or threo form independent of the configuration of 3-and4-carbon atoms, reacting the latter with a dehydrating agent to form a1,3- thiazine of the formula Y HCH CH VII COOR; Ni CCH COOR occuring inthe form of its erythro and/or threo isomers, subjecting the latter toacid hydrolysis or reaction with hydrazine for a functional exchange toform a compound of the formula COOR NK //C\ VIII C OOR occurring in theform its erythro and/or threo isomers,

selectively saponifying the latter with a basic agent to form a compoundof the formula occurring in the form of its erythro and/or threoisomers, reacting the latter with a tritylation agent to form a compoundof the formula COOR occurring in the form of its erythro and/or threoisomers and cyclizing the latter with a lactamization agent to form acompound of formula II wherein R is trityl and optionally reacting thelatter with an acidic agent to form the compound of formula II wherein Ris hydrogen.

As a modification of the process, certain intermediates may be purifiedby salification with an acid or base. For example, a compound of formulaIX in the form of its erythro and/or threo isomers may be pre' pared byreacting a compound of formula VII with hydrazine for a functionalexchange or under acidic hydrolysis conditions to form a compound offormula VIII in the form of its erythro and/r threo isomers and thenreacting the latter with an organic acid such as oxalic or hydrogenhalide to form the acid addition salt of the formula CH3 $00k wherein Xis the acid residue in the form of its erythro and/or threo isomerswhich is then treated with a base to obtain the compound of formula IX.

Also, an ester of DL 7-tritylamino-desacetoxy-cephalosporanic acid offormula II in the form of its erythro and/or threo isomers may beprepared by reacting a 1,3-thiazine of formula IX in its erythro and/orthreo form with a tritylation derivative to form a raw compound offormula X in the form of its erythro and/or threo isomers, reacting thelatter with a secondary amine to form the corresponding amine salt ofthe formula in the form of its erythro and/or threo isomers wherein H Nis a cation derived from a secondary amine and subjecting the latter toacid hydrolysis followed by cyclization with a lactamization agent toobtain the desired compound. The compounds IV, VI, VII, VIII, IX and Xpossess two asymetric carton atoms and thus can exist in the form oftheir threoisomer and erythro isomer. The threo/erythro ratio may varyas a function of the working conditions. The alkaline treatment of thea-carbalkoxy-aminomethyl-1,3-thiazine of the formula VIII existing inthe form of a mixture of threo-and erythro isomers can lead in certaininstances to a-carboxyaminomethyl- I ,3-thiazine of formula IX existingalmost exclusively in the form of its threo-isomer. It should be notedthat only the threo isomer of the a-carboxy tritylamino methyl1,3-thiazine of formula X leads through cyclization to the ester of theDL 7- tritylamino-desacetoxy-eephalosporanic acid of formula II with the6H, 7I-I-cis configuration peculiar to the derivatives of thecephalosporin of natural origin. It is most desirable to obtain themaximum of the threo isomer compound of formula X which can betransformed with very good yields into the cis-isomer of the compound offormula II.

In a preferred embodiment of the process of the invention, the acid HXin whose presence the enamine of formula III is reacted with hydrogensulfide is anhydrous hydrochloric acid. It is also possible to use othermineral acids such as sulfuric acid or a sulfonic acid such as toluenesulfonic acid or methanesulfonic acid. The tertiary amine in whosepresence is effected the condensation of the thioaminal of formula IVwith the ester of cz-keto-B-methylene-butyric acid of formula V ispreferably triethylamine. This condensation can also be performed in thepresence of other tertiary amines and particularly in the presence ofN-methylpiperidine, pyridine, trimethylamine, N-methylpyrrolidine orquinoline.

The dehydration agent, which is reacted with the 1,3- thiazane offormula VI to obtain the 1,3-thiazine of formula VII is an aqueoussolution of hydrochloric acid or oxalic acids. When Y in the1,3-thiazine of the general formula VII is a cyclic imido group, the Ygroup is preferably split off by an exchange of functions with the aidof hydrazine and when Y is a benzolyamino or a thiobenzoylamino group, ahydrogenolysis is preferably carried out. In the latter case, it is alsopossible to first effect an alkylation of the ketone or thioketonefunction with an alkyl sulfate or with Meerwein reagent to obtain thecorresponding imino ether or the thioimino ether and then in a secondstep, hydrolyze the said compound with a mineral or organic acid such asacetic acid or dilute hydrochloride acid.

The basic agent used to perform the selective saponification of thegroup COOR of the 1,3-thiazine of formula VIII is preferably lithiumhydroxide but potassium hydroxide, sodium hydroxide or an alkali metalcarbonate, such as sodiumor potassium carbonate may be used. Thetritylation agent with which the l,3-thiazine of formula IX is treatedto obtain the 1,3-thjazine of formula X is preferably trityl chlorideand this reaction is carried out in the presence of an alkaline agentand more particularly in the presence of a tertiary amine such astriethylaminc, trimethylamine, N- methylpiperidine, pyridine,N-methylpyrrolidine or quinoline.

As lactamization agent for the cyclization of the 1,3- thiazine offormula X, a dialkyl or dicycloalkylcarbodiimide such asdicyclohexyl-carbodiimide or diisopropyl-carbodiimide is used, and thereaction is carried out in a polar solvent such as nitromethane, adisubstituted amide, a sulfoxide, acetone or acetonitrile and inpresence of a tertiary amine such as pyridine, a collidine or adialkylaniline, and this medium could admit an additional solvent suchas methylene chloride or the chloroform.

The alkaline agent used to convert the erythro isomer of 1,3-thiazine offormula X to the threo isomer is an alkali metal hydroxide such assodium hydroxide, or lithium hydroxide and the reaction is performed inan alkanol such as methanol or ethanol. The acidic agent, used to obtaina compound of formula I] wherein R is H, starting from a compound offormula II wherein R is trityl is advantageously a mineral or organicacid, such as hydrochloric acid or acetic acid, and the reaction is inan organic solvent such as nitromethane, chloroform, methylene chlorideor methanol.

The compounds of formula II are particularly interesting intermediatesfor the synthesis of compounds of the family of cephalosporins withantibiotic activity. The compounds of formula II wherein R is trityl canbe detritylated with an acidic agent to obtain the corresponding 7-aminocompounds of formula II wherein R is H, which are useful intermediatesby reacting with functional derivatives of a carboxylic acid, which mayreact with amines, and then by acid hydrolysis to obtain compoundspossessing an activity analogous to that of cephalexine such asdescribed in U.S. Pat. No. 3,124,576. Besides, the compounds of formulaII wherein R is H can after reaction with phenoxyacetic acid chloride betransformed into cephalosporin V by the method described by WABBER et al[J.A.C.S., Vol. 91, (1969) 5 674].

The process of the invention thus permits total synthesis of compoundsof the type of 7-aminodesacetoxy-cephalosporanic acid which has not beenpossible without beginning with a compound having the basic nucleus.

Another feature of the invention are the novel inter mediates,thioaminals of the formula COOR;,

occurring in the form of threo and/or erythro isomers wherein X ishalogen or sulfuric-or sulfonic anion, R and Y are defined as above andparticularly the hydrochloride of thioaminal of methylphthalimidomalonaldehydate.

Also novel are derivatives of 1,3-thiazane of the formula s Y- H T V]cooR CH3 HO ooR occurring in the form of threo and/or erythro isomers,independent of the configuration of the 3 and 4 carbons wherein'R R andY are defined as above and particularly'a-rnethoxycarbonyl-2-phalimidomethyl-4-ethoxycarbonyl-4-hydroxy-5-methyl-1,3-thiazane,a-methoxycarbonyl-2-phthalimidomethyl-4-terbutoxycarbonyl-4-hydroxy-5-methyll ,3-thiazane andoz-methoxycarbonyl-Z-phthalimidomethyl-4-benzyloxycarbonyl-4-hydroxy-5-methyl-1 ,3-thiazane. Also novel are thederivatives of 1,3-thiazines of the formula and their mineral or organicacid salts occurring in the form of threo and/or erythro isomers inwhich Y is amino, a cyclic imido, a benzoylamino or a thiobenzoylaminoand R is defined as above, R;, is a linear or branched alkyl radicalwith l to 10 carbon atoms or an aralkyl radical with 7 to 15 carbonatoms, or if Y represents an amino group R is hydrogen, and particularlya-methoxycarbonyl-Z-phthalimidomethyl-4- ethoxycarbonyl5-methyl-2,3-dihydro-6H-l ,3-thiazine;a-methoxycarbonyl-Z-phthalimidomethyl-4terbutoxycarbonyl-5-methyl-2,3-dihydro-6H-1 ,3- thiazine;a-methoxycarbonyl-2-phthalimidomethyl-4-benzoyloxycarbonyl-5-methyl-2,3-dihydro-6H-1,3- thiazine;a-methoxycarbonyl-Z-aminomethyl4-ethoxycarbonyl-5-methyl-2,3-dihydroxy-6H-1,3- thiazine, its oxalate andits hydrochloride;a-methoxycarbonyl-2-aminomethyl-4-terbutoxycarbonyl-5-methyl-2,3-dihydro-6l-Ll,3-thiazine, its oxalate and its hydrochloride;a-methoxycarbonyl-2-aminomethyl-4-benzyloxycarbonyl-S-methyl-2,3-dihydro-6H-l ,3- thiazine, its oxalateand its hydrochloride; a-carboxy-Z-aminomethyl-4-ethoxycarbonyl-5-methyl-2,3-dihydro- 6H- 1 ,3-thiazine;a-carboxy-Z-aminomethyl-4- terbutoxycarbonyl-5-methyl-2,3-dihydro-6H- l,3- thiazine and a-carboxy-2-aminomethyl-4-benzyloxycarbonyl-5methyl-2,3-dihydro-6H- l ,3- thiazine.

Also novel are the derivatives ofoz-carboxytritylaminomethyl-1,3-thiazine of the formula and theirsecondary amine salts occuring in the form of threo and/or erythroisomers wherein R is defined as above and particularlya-carboxy-2-tritylaminomethyl- 4-ethoxycarbonyl-5-methyl-2,3-dihydro-6H-l ,3- thiazine and its diethylamine salts, or-carboxy-2-tritylaminomethyl-4-terbutoxycarbonyl-5-methyl-2,3-dihydro-6Hl,3-thiazine and its diethylamine salt anda-carboxy-2tritylaminomethyl-4-benzyloxycarbonyl-5-methyl-2,3-dihydro-6H-l,3-thiazine and its diethylamine salt.

It is an other object of the invention to provide a process of resolvingesters of DL-7-amino-desacetoxycephalosporanic acid of general formulain the form of cis, trans or cis-trans mixtures, wherein R is selectedfrom the group consisting of lower alkyl of 1 to 6 carbon atomsoptionally substituted with at least one chlorine and aralkyl of 7 to 15carbon atoms, comprising reacting the DL-compound of the above formulawith an optically active organic acid.

In the following examples there are described several preferredembodiments to illustrate the invention. However, it should beunderstood that the invention is not intended to be limited to thespecific embodiments.

EXAMPLE I TERT-BUTYL CIS DL 7-TRlTYLAMlNO-DESACETOXY- CEPHALOSPORANATESTEP A: SODIUM a-KETO-B-METHYLENE- BUTYRATE 65 ml of N sodium hydroxidewere added with stirring and cooling to a solution of l 1.5 g of ethyloz-keto-B-methylene-butyrate (made by process described in J. Am. Chem.Soc., 1964, p. 766) in 77 ml of dioxane and the mixture was allowed tostand for 5 minutes. The mixture was evaporated to dryness under reducedpressure and the residue triturated in 50 ml of ethanol. The mixture wasevaporated to dryness and the residue was triturated in ether, vacuumfiltered and washed with ether. The product was dried under vacuum toobtain 8.72 g of sodium a-keto-B-methylenebutyrate which was used as isfor the next step.

Analysis: C H O Na 0.25 H O; molecular weight 140.08 Calculated: %C42.89; %H 3.95; Found: C 42.7; H 3.9 U.V. Spectrum (ethanol):

Max. at 215 nm: E 542 Max. at 352 nm: E 3 STEP B: TERT.-BUTYLa-KETO-B-METHYLENE- BUTYRATE 13.6 g of sodiumoz-keto-B-methylene-butyrate were cooled for minutes at 40C and then 200ml of liquid isobutylene and 5 ml of concentrated sulfuric acid wereadded at the low temperature. The reaction mixture was allowed to returnto room temperature and was then stirred for 21 hours. After cooling to40C, excess isobutylene was removed by heating at 30C and the mixturewas evaporated to dryness. The residue was added to 100 ml of methylenechloride and 60 ml of 2N sodium hydroxide to obtain a pH of 8. Themixture was stirred and the organic phase was decanted and washed withwater. The aqueous phase was reextracted with methylene chloride and theorganic phases were combined and dried over magnesium sulfate. Themixture was vacuum filtered and the filter was washed with methylenechloride. The filtrate was evaporated to dryness under reduced pressureto obtain 13.7 g of tertbutyl aketo-B-methylene-butyrate which was usedas is for Step D. The product occurred in the form of an oily liquidsoluble in alcohols, ether and chorinated solvents and insoluble inwater. 1R Spectrum (chloroform):

Presence of CO at 1730 and 1683" and of C=C at U.V. Spectrum (ethanol)Max. at 225 nm: E 231 STEP C: THIOAMINAL OF METHYL PHTHALIMI-DO-MALONALDEHYDRATE.HC1

12 g of hydrogen sulfide, 8 g of gaseous hydrochloric acid and 50 g ofmethyl 2-phthalimido-3-aminoacrylate (obtained by process of FrenchPatent No. 1,469,529) were dissolved in 400 ml of nitromethane cooled to-10C and the mixture was then allowed to stand for 2 hours at roomtemperature. After cooling, the mixture was vacuum filtered and thesolid recovered was washed with a 50-50 nitromethane-ether mixture andthen with ether and dried to obtain a first crop of 17.1 g of thehydrochloride of thioaminal of the threo isomer of methylphthalimido-malonaldehydate. The solution was allowed to stand foranother 3 hours to obtain a second crop of 3.6 g of the said product.The mother liquor was cooled to -10C and 4 g of gaseous hydrochloricacid and 6 g of hydrogen sulfide were added thereto. The mixture wasallowed to stand overnight at room temperature to furnish a third cropof 18.6 g of product. Finally, the solution was allowed to stand for 3days to obtain a fourth crop of 3.2 g of the erythro isomer for a totalyield of 42.5 g. The product occurred in the form of colorless crystalsmelting at about 180C with decomposition and soluble in water, slightlysoluble in ethanol and methanol and insoluble in ether and chloroform.

Analysis: C H O N SCl; molecular weight 316.77: Calculated: %C 45.49; %H4.13; %N 8.85; %S 10.13; %Cl 11.20; Found: C 45.2; H 4.1; N 8.7; S 10.2;CI 11.3 1R Spectrum (Nujol):

Presence of carbonyls at 1782 and 17l8"", of

at 1748" and aromatic.

STEP D: THREO ISOMER OF a-METHOXYCARBO- NYL-2-PHTHALlMlDOMETHYL-4-TERT.-BUTOXYCARBONYL-5-METHYL-2,3- DIHYDRO-6H-1,3-TH1AZ1NE A mixture of 32.8 gof tert-butyl a-keto-B- methylenebutyrate, 100 ml of dioxane and 43 g ofthe hydrochloride of the thioaminal of methyl phthalimidomalonaldehydate(first crop of Step C) was cooled to ether. the mixture was vacuumfiltered. The filter was washed with ether and the combined filtrateswere evaporated to dryness. The residue was dissolved in 135 ml ofethanol and 13 ml of water and then 12 cc of N hydrochloric acid wereadded to the solution. Crystallization began and the mixture was stirredfor one hour under a nitrogen atmosphere and then vacuum filtered. Therecovered precipitate was washed with ethanol cooled to -40C and thenwith petroleum ether and dried to obtain 27.4 g of the threo isomer ofa-methoxycarbonyl-2-phthalimidomethyl-4-tertbutoxycarbonyl-S-methyl-2,3-dihydro-6H-1,3-thiazine.By concentration of the mother liquors, a second crop of 2.5 g of theproduct were obtained for a total yield of 29.9 g of the threo isomer.The product occurred in the form of yellow crystals melting at 138C andsoluble in chloroform, slightly soluble in ethanol and ether andinsoluble in water.

Analysis: C H O N S; molecular weight 432.5: Calculated: %C 58.33; %H5.59; %N 6.48; %S 7.40; Found: C 58.5; H 5.4; N 6.4; 7.6 U.V. Spectrum(ethanol):

Max. at 219 nm: E 964; F41,500 lnflex. towards 231 nm: E 459 lnflex.towards 239 nm: E 274 Max. at 290 290 E 117; F5,050 STEP E: ERYTHROISOMER OF a-METHOXYCAR- BONYL-Z-PHTHALIMIDOMETHYL-4-TERTBUTOXYCARBONYL-5-METHYL-2,3-

DlHYDRO-6H-l ,3-THIAZINE 1.75 ml of triethylamine were added to asuspension of 2.55 g of tert.-butyl a-keto-B-methylene-butyrate and 3.96g of the hydrochloride of the thioaminal of methylphthalimidomalonaldehydate (fourth crop of stage C) in 12 ml of ethanolcooled to between 0 and -C and the mixture was allowed to stand at roomtemperature for 90 minutes. Crystallization was started and allowed tocontinue for 30 minutes. The mixture was vacuum filtered and therecovered precipitate was washed with ethanol and then with petroleumether and dried under reduced pressure. The reisdue was passed oversilica to obtain 1.9 g of the erythro isomer ofa-methoxycarbonyl-2-phthalimidomethyl-4-tertbutoxycarbonyl-S-methyl-2,3'dihydro-6H-1,3thiazinemelting at 138C. The product occurred in the form of pale yellowcrystals soluble in chloroform, slightly solu ble in ethanol and etherand insoluble in water.

Analysis: C ,H O N S; molecular weight 432.5: Calculated: %C 58.33; %H5.59; %N 6.48; %S 7.40; Found: C58.2; H 5.5; N 6.5; S 7.4 U.V. Spectrum(ethanol):

Max. at 219 nm: E 1042 lnflex towards 23132 nm: E 392 Max. at 239 nm: E270 Max. at 291 nm: E 120; F5,200

Inflex. towards 301 nm: E 100 STEP F: THREO AND ERYTHRO ISOMERS OF a-C-ARBOXY-2-AMlNOMETHYL-4-TERT- BUTOXYCARBONYL-5-METHYL-2,3-

DlHYDRO-6H- l ,3-THIAZINE A mixture of 28 g of the threo isomer ofa-methoxycarbony-2-phthalimidomethyl-4-tert-butoxycarbonyl5-methyl-2,3-dihydro-6H-l,3-thiazine, 340 ml of chloroform, 65 ml ofmethanol and 39 ml of a solution of 5 g of hydrazine hydrate in 50 ml ofmethanol was refluxed overnight under a nitrogen atmosphere withagitation and was then cooled and filtered. The filter was rinsed withmethylene chloride and the combined filtrates were evaporated todryness. The residue was taken up in ml of ether and the mixture wasstirred for 10 minutes under a nitrogen atmosphere and was thenfiltered. The filter was rinsed with ether and the filtrate was treatedwith carbon black, stirred for 5 minutes under a nitrogen atmosphere andwas vacuum filtered. The filter was rinsed again with ether and thefiltrates were concentrated to dryness.

The residue was dissolved in 33 ml of dioxane and 16 ml of water wereadded thereto. After cooling the mixture to 0C, 62.5 ml of N lithiumhydroxide were added while keeping the temperature between 0 and 2C. Themixture was stirred for 5 minutes under a nitrogen atmosphere and the pHwas then adjusted to 6 by addition of acetic acid. The mixture wasreduced to a small volume under reduced pressure and after the additionof 65 ml of acetone, the mixture was stirred for 5 minutes and was thenvacuum filtered. The precipitate was washed with acetone and then etherand dried to obtain 5.83 g of the threo isomer of a-carboxy-Z-aminomethyl-4-tert-butoxy-carbonyl-5-methyl-2,3- dihydro-6H-1,3-thiazinemelting towards 200C with decomposition. The product occurred ascolorless crystals soluble in acidic water, slightly soluble in ethanoland insoluble in ether.

To recover the erythro isomer, the mother liquors were concentratedwithout removing water and were then added to ether. The mixture wasstirred for 1 hour at room temperature and was then vacuum filtered. Theprecipitate was washed with ether, empasted with ether and then withwater and finally with ether. The product was dried at room temperatureunder reduced pressure to obtain 5.27 g of the erythro isomer in theform of yellow crystals melting towards C with de composition.

Analysis: C, H O N S /2 H O; molecular weight 297.36; Calculated: %C48.46; %H 7.12; %N 9.42; %S 10.78; Found: C 48.4; H 6.9; N 9.4; S 10.4A. THREO ISOMER IR Spectrum (Nujol); Presence of C O ester at 1727 U.V.Spectrum (ethanol): Max. at 280nm: E

B. ERYTHRO ISOMER 1R Spectrum (Nujol): Presence of carbonyl at 1718 and1689 U.V. Spectrum (ethanol): Max. at 282 nm: E

STEP G: THREO ISOMER OF a-CARBOXY-2- TRITYLAMINOMETHYL-4-TERT-BUTOXYCARBONYL-5-METHYL-2,3-

DlHYDRO-6l-L l ,3-THIAZINE A mixture of 6.62 g of the threo isomer ofa-carboxy- 2-aminomethyl-4-tert-butoxycarbonyl-S-methyl-2,3-dihydro-6H-1,3-thiazine in 46 ml of chloroform was cooled to -4C withagitation under a nitrogen atmosphere and a solution of 10.4 g of tritylchloride in 30 ml of chloroform and 30 ml of a 2 M triethylamine inchloroform solution were added thereto. The mixture was allowed to standfor 3 hours while cooling and the temperature of the reaction mixturewas allowed to rise to 20C with stirring. The mixture was thenconcentrated to dryness and the residue was taken up in 110 ml of etherand 45 ml of water. The mixture was stirred and decanted and the etherphase was washed with a mixture of 45 ml of water and 22 ml of Nhydrochloric acid with agitation. After decanting, the aqueous phaseswere reextracted with ether and the combined ether phases wereconcentrated to dryness under reduced pressure. The residue wastriturated with 23 ml of ether and 23 ml of methanol were added thereto.The mixture was stirred for 20 minutes and then was vacuum filtered. Theprecipitate was washed with a 1 l ethermethanol mixture, then with etherand dried to obtain 7.38 g of the threo isomer of a-carboxy-Z-tritylaminomethyl-4-tert-butoxycarbonyl-S-methyl- 2,3-dihydro-6H-l,3-thiazine.

The mother liquors were concentrated to a small volume and 90 mlisopropyl ether and then 1.8 ml of 4N lithium hydroxide were addedthereto. The mixture was stirred and after 9 ml of water were addedthereto, stirred again. The mixture was decanted and the organic layerwas acidified to a pH of 4 with acetic acid addition and then wasextracted with a mixture of 18 ml of methanol and 9 ml of water and thenwith water. The aqueous methanol phase was acidified to pH 4 by aceticacid addition and the methanol was evaporated off. The mixture wasvacuum filtered and the precipitate was washed with water and dried. Theresidue was empasted with ml of methanol and was vacuum filtered. Theresidue was washed with methanol and then ether and dried to obtain asecond crop of 860 mg of the said threo isomer making a total yield of8.24 g melting of 2lO-220C with decomposition. The prod uct occurred inthe form of colorless crystals soluble in chloroform, insoluble in waterand methanol and slightly soluble in ethanol and ether.

Analysis: C H O N S; molecular weight 530.70: Calculated: %C 70.15; %H6.45; %N 5.28; %S 6.05; Found: C 69.9; H 6.6; N 5.5; S 6.3 1R Spectrum(Nujol):

Presence of conjugated ester and acid at 1703 and l69l of C C at 1643"and of aromatic. U.V. Spectrum (ethanol):

lnflex. towards 227 nm: E, 274

lnflex. towards 255 nm; E 53 Max. at 263 nm: E 53 Max. at 272 nm: E 54Max. at 285 nm: E 57 STEP H: TRITYLATION OF ERYTHRO lSOMER ANDCONVERSION TO THREO 1SOMER A solution of 8.1 g of trityl chloride in 24ml of chloroform and then 23.4 ml of a chloroform solution of 2Mtriethylamine were added to a suspension of 5.22 g of the erythreoisomer obtained in a preceding step in 36 ml of chloroform cooled to 5Cand the mixture was allowed to stand for 3 hours with cooling and thenat room temperature for 30 minutes. The mixture was concentrated todryness under reduced pressure and the residue was taken up in 100 ml ofether and 20 ml of water. The aqueous phase was decanted and ml of waterand ml of N hydrochloric acid were added to the organic phase which wasstirred and again decanted. The aqueous phase was reextracted with etherand the combined ether phases were dried over sodium sulfate and werevacuum filtered. The filtrate was evaporated to dryness and the residuewas dissolved in 100 m1 of isopropyl ether and 20 ml of methanol. Afterthe addition of 4.5 ml of 4N lithium hydroxide, the mixture was stirredand 20 ml of water added. The mixture was decanted and the aqueousmethanolic phase was acidified by the addition of acetic acid. The etherphase was reextracted with methanol and water and the combined aqueousmethanol phases were acidified after which the methanol was evaporatedunder reduced pressure. The aqueous phase was extracted with chloroformand the chloroform phase was dried over sodium sulfate and evaporated todryness. The residue was taken up in 5 ml of ether and 2 ml of methanoland the mixture was vacuum filtered. The residue was washed with etherand dried to obtain 1.28 g of the threo isomer identical to the productof the preceding step.

I. TERT-BUTYL CIS DL 7-TR1TYLAM1NO- DESACETOXY-CEPHALOSPORANATE Asolution of 3.36 g of dicyclimide (dicyclohexylcarbodiimide) in 20 ml ofchloroform was added under a nitrogen atmosphere to a cooled suspensionof 7.44 g of the threo isomer of a-carboxy-Z-tritylaminomethyl-4-tert-butoxycarbonyl-5-methyl-2,3-dihydro-6H,l,3-thiazine in 700 ml of nitromethane and the mixturewas stirred for 15 minutes under the nitrogen atmosphere. 14 ml ofpyridine were added to the mixture which was then stirred overnightunder a nitrogen atmosphere and then for 1 hour at 25C. The

mixture was vacuum filtered and the filter was rinsed with ether afterwhich the filtrate was evaporated to dryness under reduced pressure. Theresidue was taken up in 50 ml of a l-l ether-methylene chloride mixturewhich was vacuum filtered. The filtrate was evaporated to dryness andthe residue was stirred with 23 ml of ether. 23 ml of isopropyl etherwere added thereto and the mixture was iced and vacuum filtered. Theprecipitate was washed with isopropyl ether and dried to obtain 5.34 gof the tert-butyl ester of cis DL 7-tritylamino-desacetoxy-cephalosporanic acid melting at 204C. The productoccurred as colorless crystals soluble in chloroform, slightly solublein ether and methanol and insoluble in water.

Analysis: C H O N S; molecular weight 5 12.7: Calculated: %C 72.62; %H6.29; %N 5.46; %S 6.25; Found: C 72.3; H 6.3; N 5.5; S 5.9

U.V. Spectrum (ethanol):

lnflex towards 225 nm: E 329 Max. at 265 nm: E 1 l7 =6,000

EXAMPLE [I ETHYL ClS AND TRANS DL 7-TRlTYLAMINO-DESACETOXY-CEPHALOSPORANATE STEP A: THREO lSOMER OF a-METHOXYCARBO-NYL-Z-PHTHALIMlDOMETHYL-4- ETHOXYCARBONYL-4-HYDROXY-5-METHYL-1,3-TH1AZANE 1.65 ml of ethyl a-keto-B-methylene-butyrate (obtained byprocess of J. Am. Chem. Soc., 1964, p. 766) and 3.16 g of thehydrochloride of the thioaminal of methyl phthalimido-malonaldehydate(first crop of Step C of Example 1) followed by 1.3 ml of triethylaminewere added to 10 ml of ethanol cooled to l5C while maintaining the saidtemperature and the reaction mixture was allowed to return to roomtemperature where it was held for 30 minutes. Sufficient methylenechloride was added to effect total dissolution and the mixture wasconcentrated to dryness. The residue was dissolved in methylene chlorideand the organic phase was washed with water. The aqueous phases werereextracted with methylene chloride and the combined organic phases weredried over magnesium sulfate and were vacuum filtered. The filter waswashed with methylene chloride and the filtrate was evaporated todryness. The residue was taken up in 15 ml of ethanol andcrystallization was started. The mixture was then vacuum filtered andthe precipitate was washed with ethanol and then ether and dried. 1.9 gof the residue were dissolved in 6 ml of methylene chloride and thesolution was vacuum filtered. The filter was washed with methylenechloride and the filtrate was reduced to a small volume. After theaddition of ml of ethanol, crystallization was started and the mixturewas vacuum filtered. The precipitate was washed with ethanol, then etherand dried to obtain 1.64 g of the threo isomer of a-methoxycarbonyl-Z-phthalimidomethyl-4-ethoxycarbonyl-4-hydroxy-5- methyl-l ,3thiazanemelting at 152C. The product occurred in the form of colorless crystalssoluble in chloroform and methylene chloride, slightly soluble inethanol and insoluble in water and ether.

Analysis: C H O N S; molecular weight 422.47: Calculated: %C 54.02; %H5.25; %N 6.63; %S 7.58; Found: C 53.8; H 5.2; N 6.5; S 7.8 IR Spectrum(chloroform):

Presence of NH at 3298", of OH at 353l" of C=O at 1742, 1725 and 1779""and of aromatic at 1615''.

STEP B: THREO lSOMER OF oz-METHOXYCARBO- NYL-Z-PHTHALIMlDOMETHYL-4-ETHOXYCARBONYL-5-METHYL2,3- DlHYDRO-oH-l ,3-TH1AZINE A mixture of 422 mgof the threo isomer ofa-methoxycarbonyl-2-phthalimidomethyl-4-ethoxycarbonyl4-hydroxy-S-methyll ,3-thiazane, 1.5 ml of 90% ethanol,

0.5 ml of methylene chloride and a drop of N hydrochloric acid stood for1 hour at room temperature and after evaporation of the methylenechloride, the mix ture was vacuum filtered. The precipitate was washedwith 75% ethanol and dried to obtain 176 mg of the threo isomer ofa-methoxycarbonyl-2- phthalimidomethyl-4-ethoxycarbonyl-5-methyl-2,3-dihydro-6H-l ,3-thiazine.

The mother liquors stood overnight and were than vacuum filtered. Theprecipitate was washed with 75% ethanol and then with petroleum ether toobtain a second crop of 103 mg of the said threo isomer for a totalyield of 279 mg. The product occurred in the form of yellow crystalsmelting at 120C and was soluble in chlorinated organic solvents,slightly soluble in ethanol and insoluble in water.

Analysis: C H O N S; molecular weight 404.45: Calculated: %C 56.43 %H4.99 %N 6.93 %S 7.91; Found: C 56.6; H 5.2; N 6.9; S 7.7 U.V. Spectrum(ethanol):

Max. at 219-220 nm: E 1,050

lnflex. towards 239-240 nm: E,

Max. at 290 nm: E 125 STEP B: ERYTHRO ISOMER OF a-METHOXYCARBONYL-2-PHTHALIM1DOMETHYL4 ETHOXYCARBONYL-5-METHYL-2,3-

5.5 ml of ethyl oz-keto-B-methylene-butyrate and 10.5 g of thehydrochloride of the thioaminal of methyl phthalimidomalonaldehydate(4th crop of Step C of Example 1) were added to 33 ml of ethanol cooledto 5C and was stirred under a nitrogen atmosphere at -l 5C. 4.6 m1 oftriethylamine were added while keeping the temperature at C and afterletting the temperature rise to 27C, 2 ml of N hydrochloric acid wereadded thereto. The mixture was allowed to stand for 30 minutes and wasvacuum filtered. The precipitate was washed with ethanol cooled at 50Cand then with petroleum ether and dried to obtain 1 1.2 g of rawproduct. The mother liquors were allowed to stand over night to get asecond crop of 3.9 g of product. The two crops were dissolved in 25 mlof methylene chloride and after the addition of ml of ethanol, themethylene chloride was evaporated. The mixture was vacuum filtered andthe precipitate was washed with ethanol and then petroleum ether toobtain 8.95 g of the erythro isomer of a-methoxycarbonyl-Z-phthalimidomethyl-4-ethoxycarbonyl-5-methyl-2,3- dihydro-l,3-thiazinemelting at C.

1R Spectrum (chloroform):

Presence of carbonyls at 1779 and 1722 of N-C- COOR at 1746 and of NH at3413""? U.V. Spectrum (ethanol):

Max. at 219 nm: E 1,120; c=45,500

lnflex. towards 239240 nm: E 292 Max. at 291 nm: B 141; c=5,700

lnflex. towards 299 nm: E 125 Using the same procedure, 31.7 g of thehydrochloride of the thioaminal of methyl phthalimidomalonadehydate(mixture of different-crops from Example 1) was reacted to obtain amixture the threo and erythro isomers of a-methoxycarbonyl-Z-phthalimidomethyl-4-ethoxycarbonyl-5-methyl-2,3- dihydro-1,3-thiazinemelting at 100C.

STEP C: HYDROCHLORIDE OF THREO lSOMER OF a-METHOXYCARBONYL-2-AMINOMETHYL-4-ETHOXYCARBONYL5- METHYL-2,3-Dl1-1YDRO-6H-l,3-THIAZ1NE Amixture of 4.04 g of the threo isomer of Step 13, 52

ml of chloroform, 10 ml of methanol and 6 ml of a solution of 10 g ofhydrazine hydrate in 100 ml of chloroform was refluxed overnight withstirring under a nitrogen atmosphere and after cooling, the mixture wasvacuum filtered. After washing the filter with methylene chloride, thecombined organic phases were concentrated to dryness. The residue wasadded to 5 ml of water and after adding 10.5 ml of N hydrochloric acid,the mixture was vacuum filtered. The filter was washed with water andthe aqueous phase was evaporated to dryness. The residue was added to 3ml of ethanol to which 10 ml of ether were then added and the mixturewas vacuum filtered. The residue was washed with an 80-20 mixture ofether-ethanol and then ether to obtain 1.28 gm of the hydrochloride ofthe threo isomer of a-methoxycarbonyl-Z-aminomethyl-4-ethoxycarbonyl-5-methyl-2,3-dihydro-6H-1,3-thiazine. The mother 1iquors wereconcentrated to dryness and the residue was treated with ethanol andether to obtain a second crop of 290 mg of the said threo isomer for atotal yield of 1.57 g. The product occurred in the form of colorlesscrystals melting at C and soluble in water and ethanol and slightlysoluble in ether.

Analysis: C H O N SCl; molecular weight 310.8: Calculated %C 42.51 %1-16.16 %N 9.02 %S 10.30 %Cl 11.41; Found C 42.6; H 6.3; N 8.8; S 10.0; C]11.4 1R SPECTRUM(Nujol):

Presence of carbonyl at l752"' of conjugated ester at 1681" and of C=Cat 1637"".

U.V. Spectrum (ethanol):

lnflex. towards 226 nm: E 90 Max. at 277nm: E 109; e 3400 STEP C:OXALATE OF ERYTHRO ISOMER OF a-METHOXYCARBONYL-2-AMlNOMETl-lYL-4-ETHOXYCARBONYL--METHYL2.3- DlHYDRO-6H-1,3-TH1AZINE A mixture of 6.07 gof erythro isomer ofa-methoxycarbonyl-2-phtalimidomethyl-4-ethoxycarbonyl5-methyl-2,3-dihydro-6H-1,3-thiazine from Step B, 79 ml of chloroform, 15ml of methanol and 9 ml of a solution of 10 g of hydrazine hydrate in100 ml of methanol was refluxed overnight with stirring under a nitrogenatmosphere and after cooling, the mixture was vacuum filtered. Thefilter was rinsed with methylene chloride and the combined filtrateswere evaporated to dryness. The residue was triturated with 40 ml ofethyl acetate and vacuum filtered. The filter was washed with ethylacetate and the filtrate was treated with activated carbon, andfiltered. The filter was washed with ethyl acetate and 1.85 g of oxalicacid. 2H O was added to the filtrate after which crystallization waseffected. After stirring for minutes under nitrogen atmosphere, theprecipitate was vacuum filtered, washed with ethyl acetate and dried toobtain 4.74 g of the oxalate of the erythro isomer ofoz-methoxycarbonyl-2-aminomethyl-4-ethoxycarnyl-S-methyl-2,3-dihydro-6H-1,3thiazine melting at 140C.

Analysis: C H O N S; molecular weight 364.38: Calculated: %C 42.86; %H5.53; %N 7.69; %S 8.78; Found C 42.0; H 5.5; N 7.9; S 8.8 [R Spectrum(Nujol):

Presence of carbonyl at 1733" U.V. Spectrum (ethanol):

Max. at 280 nm: E 86 STEP D: a-CARBOXY-2-AMINOMETHYL-4-ETHOXYCARBONYL-5-METHYL-2,3-

DlHYDRO-6H-1,3-TH1AZINE A mixture of 20.2 g of the threo and erythromixture of the product of Step B, 260 ml of chloroform, 50 ml ofmethanol and 30 ml-of a solution of 10 g of hydrazine hydrate in 100 mlof methanol was refluxed overnight with stirring under a nitrogenatmosphere and after cooling, the mixture was vacuum filtered. Thefilter was rinsed with methylene chloride and the coinbined filtrateswere concentrated to dryness. The residue was taken up in 150 ml ofether and after stirring 15 minutes, the mixture was vacuum filtered.The filter was rinsed with ether and the combined filtrates were treatedwith activated carbon, stirred for 10 minutes and vacuum filtered. Thefilter was washed with ether and the precipitate was dried to obtain 14g of a mixture of threo and erythro isomers ofa-methoxycarbonyl-2-aminomethyl-4-ethoxycarbonyl-5-methyl-2,3-dihydr0-6H-l ,3-thiazine.

A mixture of the 14 g of raw product, 25 ml of ethanol and 25 ml ofwater was cooled and 1 1.25 ml of 4N lithium hydroxide were addedthereto after which the mixture was allowed to stand for minutes. 4 mlof concentrated hydrochloric acid were added thereto and the mixture wasleft at room temperature with crystallization starting. The mixture wasstirred for 30 minutes under a nitrogen atmosphere and then 150 m1 of a50-50 ether-tetrahydrofuran mixture were added. After standing for 10minutes, the mixture was vacuum filtered and the precipitate was washedwith acetone, then ether and dried to obtain 7 g of principally thethreo isomer of a-carboxy-2-aminomcthyl-4-cthoxycarbonyl-5-methyl-2,3-dihydro-6H-1,3-thiazine melting at 160C withdecomposition. The product occurred in the form of creamy white crystalssoluble in ethanol, slightly soluble in water and acetone and insol ublein ether.

Analysis: C, H, O N S.O.5H O; molecular weight 269.32 Calculated: %C44.60 %H 6.37 %N 10.40 %S 11.90; Found: C 44.4; H 6.4; N 10.1; S 11.2 IRSpectrum (Nujol):

Bands at 3478, 3287, 1727, 1675, 1637 and 1595"" U.\/. Spectrum(ethanol):

Max. at 280281 nm: E 126 Using the same procedure, the hydrochloride ofthe threo isomer of a-methoxycarbonyl-2-aminomethyl-4-ethoxycarbonyl-5-methyl-2,3-dihydro-6l-l-1 ,3-thiazine of Step C and theoxalate of corresponding erythro isomer of Step C were reacted in thepresence of lithium hydroxide to obtain the corresponding threo anderythro isomers of oz-carboxy-Z-aminomethyl-4-ethoxycarbonyl-5-methyl-2,3-dihydro-6H- l ,3-thiazine. STEP E:DIETHYLAMINE SALT OF THREO ISO- MER OF a-CARBOXY-Z- TR1TYLAMlNOMETHYL-4-ETHOXYCARBONYL-S-METl-1YL-2,3-

A mixture of 2.6 g of the threo isomer of a-carboxy-2-aminomethyl-4-ethoxycarbonyl-S-methyl-2,3- dihydro-6H-l,3-thiazine and20 ml of chloroform was cooled to 3C and then 12.5 ml of a solution of5.6 ml of triethylamine in 20 ml of chloroform followed by a solution of4.2 g of trityl chloride in 20 ml of chloroform were added thereto whilemaintaining an internal temperature of 0C. The mixture stood for 55minutes and the organic phase was washed with a mixture of water and Nhydrochloric acid (50-12) and then with water. The aqueous phases werereextracted with methylene chloride and the combined organic phases weredried over sodium sulfate and vacuum filtered. The filter was washedwith methylene chloride and the filtrate was evaporated to dryness. Theresidue was dissolved in 40 ml of ether and 0.8 ml of diethylamine wereadded with cooling. Crystallization was induced and after standing 10minutes, the mixture was vacuum filtered. The precipitate was washedwith ether and dried to obtain 2.715 g of the diethylamine salt ofprincipally the threo isomer of a-carboxy-2-tritylaminomethyl-4-ethoxycarbonyl-5-methyl-2,3 dihydro-6H-1 ,3-thiazinemelting at 150C. The product occurred in the form of colorless crystalssoluble in chloroform. slightly soluble in methanol and insoluble inwater and ether.

Analysis: C H O N S; molecular weight 575.78: Calculated: %C 68.85; %l-17.18; %N 7.30; %S 5.55; Found: C 67.6; H 7.1; N 7.1; S 5.2 IR Spectrum(chloroform):

Bands at 3292, 1722, 1696, 1634 and 1601"" U.V. Spectrum (ethanol):

lnflex. towards 230 nm: E

Max. at 288 nm: E 50 STEP F: ETHYL ESTER OF CIS AND TRANS DL 7-TRlTYLAMlNO-DESACETOXYCEPHALOSPO- RANlC ACID 20 ml of 0.5 N hydrochloricacid were added to a solution of 2.3 g of the diethylamine salt obtainedin Step E in 40 m1 of chloroform and the aqueous phase was decanted. Theorganic phase was washed with water and the combined aqueous phases werereextracted with chloroform. The organic phase was dried over sodiumsulfate and evaporated to dryness. The residue was dissolved in ml ofether and the solution was treated with activated carbon and filtered.The filtrate was evaporated to dryness and the residue was taken up in200 ml of nitromethane. 0.88 g of dicyclohexylcarbodiimide were added tothe cooled solution and the mixture was allowed to stand at C for 4hours after which 2 ml of pyridine were added thereto. After standingovernight at room temperature, the mixture was vacuum filtered and thefiltrate was concentrated to dryness at 30C under reduced pressure. Theresidue was taken up in ether and the solution was filtered andevaporated to dryness. The residue was taken up in volumes of methanoland half of the methanol was evaporated. 2 ml of ether were added to themixture and crystallization occurred over 1 hour after which the mixturewas vacuum filtered. The precipitate was washed with methanol containingether and was dried to obtain 0.7 g of the ethyl ester of cis DL 7tritylamino-desacetoxy-cephalosporanic acid melting at 184C. The productoccurred in the form of colorless crystals soluble in chloroform,slightly soluble in ethanol and ether insoluble in water.

By concentration of the mother liquors and chromotography of the residueover silica gel and elution with methylene chloride containing 5% etherand crystallization from methanol, 120 mg of the corresponding transcompound melting at 174C were obtained. Analysis of CIS: C H O N S;molecular weight 484.53: Calculated: %C 71.88 %H 5.83 %N 5.78 %S 6.60;Found: C 71.5; H 5.7; N 5.7; S 6.8 U.V. Spectrum (ethanol):

lnflex. towards 227 nm: E 340 Max. at 260 nm: E 130; e 6300 B. TRANSlnflex. towards 226 nm: E 340 Max. at 263-64 nm: E 132; 6 6400 EXAMPLE111 BENZYL ESTER OF DL 7-TR1TYLAMlNO-DESACETOXY-CEPHALOSPO- RANIC ACIDSTEP A: THREO ISOMER OF a-METHOXYCARBO- NYL-2-PHTHALIMIDOMETHYL-4-BENZYLOXYCARBONYL-4-HYDROXY-5- M ETHYL- 1 ,3-THIAZANE 31.6 g of thehydrochloride of the thioaminal of methyl phthalimido-malonaldehydate(lst and 2nd crops of Step C of Example I) and then 14 ml oftriethylamine were added at 1C to 21.9 g of benzyla-keto-B-methylene-butyrate (obtained by process of J. Am. Chem. Soc.,1964, p. 791 and then the mixture was vacuum filtered when thetemperature returned to room temperature. The precipitate was washedwith ethanol and dried to obtain 33 g of the threo isomer ofa-methoxycarbonyl-2-phthalimidomethyl-4-benzyloxycarbonyl-4-hydroxy-5-methyl-1,3-thiazane which was used as isfor the next step.

For analysis, the product was crystallized from a methylenechloride-methanol mixture to obtain the product in the form of yellowcrystals melting at 180C and soluble in chloroform, slightly soluble inether and methanol and insoluble in water. Concentration of the motherliquors to dryness, dissolution in methanol and addition of Nhydrochloric acid gave 1.8 g of the erythro isomer.

Analysis: C H O N S; molecular weight 484.53: Calculated: %C 59.50; %H4.99; %N 5.78; %S 6.61; Found: C 58.9; H 4.9; N 5.8; S 6.4 STEP B: THREOISOMER OF a'METl-lOXYCARBO- NYL-2-PHTHALlMIDOMETHYL-4-BENZYLOXYCARBONYL-S-METHYL-Z,3-

DIHYDRO-6H-1,3-Tl-1IAZINE 12 ml of water and 2.5 ml of N hydrochloricacid were added to a solution of 24.2 g of the threo isomer ofa-methoxycarbonyl-2-phtalimidomethyl-4-benzyloxycarbonyl-4-hydroxy-5-methyl-l ,3-thiazane in ml of dioxane andafter standing for 45 minutes at room temperature, the solvent wasevaporated under reduced pressure. The residue was dissolved in 50 ml ofmethylene chloride and the organic solution was washed with water. Theaqueous phase was reextracted with methylene chloride and the combinedorganic phases were dried over magnesium sulfate and was vac uumfiltered. The filtrate was evaporated to dryness to obtain 23.9 g of thethreo isomer ofa-methoxycarbonyl-2-phthalimidomethyl-4-benzyloxycarbonyl-S-methyl-2,3-dihydro-6l-I-l,3-thiazine which was used as is for Step C.

STEP B: ERYTHRO ISOMER OF a-METHOXYCA- RBONYL-2-PHTl-lALlMlDOMETHYL-4-BENZYLOXY CARBONYL-5-METHYL-2,3- D1l-lYDRO-6H-1,3-Tl-1IAZINE 3.16 g ofthe hydrochloride of the thioaminal of methylphthalimido-malonaldehydate (4th crop of Step C of Example 1) and then1.4 ml of triethylamine were added to a mixture of 2.55 g of benzyla-keto-B- methylene butyrate and 10 ml of ethanol cooled to 10C andafter the reaction mixture returned to room temperature, the solutionwas evaporated to dryness.

The residue was taken up in methylene chloride and 20 ml of water wereadded followed by decanting. The

aqueous phase was reextracted with methylene chloride and the combinedorganic phases were dried over magnesium sulfate, vacuum filtered andconcentrated to dryness. The residue was dissolved in 20 ml of methanoland 0.5 ml of N hydrochloric acid were added thereto. Crystallizationwas induced and after 10 minutes standing, the mixture was vacuumfiltered and the crystals were washed with methanol and dried to obtain2.61 g of the erythro isomer of a-methoxycarbonyl-2-phthalimidomethyl-4-benzyloxycarbonyl-5-methyl-2,3-

dihydro-6H-1,3-thiazine. Concentration of the mother liquor to drynessgave a second yield of 770 mg of the said erythro isomer for a totalyield of 3.38 g.

For analysis, the product was crystallized by dissolution in methylenechloride and precipitation with methanol to obtain the product in theform of yellow crystals melting at 138C and soluble in chloroform,slightly soluble in methanol, ethanol and ether and insoluble in water.Analysis: C H O N S; molecular weight 466.52:

Calculated: %C 61.80; %H 4.75; %N 6.01; %S 6.86;

Found: C 61.5; H 4.7; N 5.9; S 6.7 STEP C: a-CARBOXY-2-AM1NOMETHYL-4-BENZYLOXYCARBONYL-S-METHYL-2,3-

50 ml of methanol and 30 ml of a 2M hydrazine hydrate methanolicsolution were added to a solution of 23.9 g ofa mixture of the threo anderythro isomers obtained in Step B and B of a-methoxycarbonyl-Z-phthalimidomethyl-4-benzyloxycarbonyl-S-methyl-2,3-dihydro-6H-1,3-thiazine in 250 ml of chloroform and the mixture wasrefluxed overnight under an nitrogen atmosphere. After cooling, themixture was vacuum filtered and the filtrate was evaporated to dryness.The residue was stirred for 15 minutes with 130 ml of ether and then wasvacuum filtered. The filtrate was treated with activated carbon, stirredfor 15 minutes and then vacuum filtered. The ether solution wasconcentrated to dryness to obtain 15.9g of a mixture of threo anderthyro isomers of a-methoxycarbonyl-2-aminomethyl-4-benzyloxycarbonyl-5-methyl-2,3-dihydro-6H- l ,3- thiazine.

The said 15.9g of product were dissolved in 25 ml of dioxane and ml ofwater were added thereto 12.5 ml of 4N lithium hydroxide were added tothe cooled mixture which was allowed to stand for 10 minutes. The pH ofthe mixture was adjusted to 4 by addition of concentrated hydrochloricacid and the dioxane was evaporated. Then, 80 ml of ether and 10 ml ofwater were added and the mixture was stirred for 2 hours and was vacuumfiltered. The precipitate was empasted with ether and then with waterand finally with ether and dried at 45C under reduced pressure. Theresidue was taken up in 99 ml of ethanol with agitation, was vacuumfiltered and dried to obtain 8.5 g of a-carboxy-Z-aminomethyl-4-benZyloxycarbonyl-5-methyl-2,3- dihydro-6I-I-l,3-thiazine. Concentration of the mother liquors gave a second crop of0.43 g of the said product for a total yield of 8.93 g.

For analysis, the product was dissolved in 10 volumes of ethyl acetatecontaining 5% of water and a slight excess of triethylamine and the pHwas adjusted to 4 by addition of acetic acid. The mixture was vacuumfiltered and the precipitate was washed with ethanol, then ether anddried to obtain the product in the form of cream crystals melting at160C with decomposition which were soluble in dilute aqueous sodiumhydroxide, slightly soluble in ethanol and insoluble in water and ether.

Analysis C H O N S.O.7H O; molecular weight 335.0: Calculated: %C 53.78%H 5.83 %N 8.36 %S 9.57; Found: C 53.7; H 5.6; N 8.5; S 9.1 IR Spectrum(Nujol):

Bands at 1701 (carbonyl)and at 1611"" U.V. Spectrum (ethanol):

Max. at 283 nm: E 106 STEP D: BENZYL ESTER OF DL 7-TRITYLAMINO-DESACETOXY-CEPHALOSPORANIC ACID A solution of 5.6 ml of triethylamine in15 ml of chloroform and then a solution of 4.2 g of trityl chloride in20 ml of chloroform were added to a suspension of 3.224 g ofa-carboxy2-aminomethyl-4- benzyloxycarbonyl-5-methyl-2,3-dihydro-6H-1,3-thiazine in 20 ml of chloroform cooled to +3C and the mixture wasstirred for 1 hour at 6C. The organic phase was washed with 50 ml ofwater containing 16 ml of N hydrochloric acid, then with ml of water andconcentrated to dryness. The residue was taken up in 100 ml of ether andthe solution was filtered and evaporated to dryness. The residue wastaken up in 60 ml of isopropyl ether and 40 ml of methanol and after theaddition of 4 ml of 10% aqueous sodium bicarbonate solution and 16 ml ofwater, the mixture was stirred and decanted. The aqueous phase wasreextracted with isopropyl ether and the methanol was removed from thecombined aqueous methanol phases which were then acidified by additionof acetic acid. The mixture was vacuum filtered and the precipitate waswashed with water and dried to obtain 2.06 g of acarboxy2-tritylaminomethyl-4-benzyloxycarb0nxyl-5-methyl-2,3-dihydro-6H-1,3-thiazine.

1.68 g of the said raw thiazine were dissolved in 168 ml of nitromethanecooled to 0C and then 0.66g of dicyclohexyl carbodiimide were addedthereto. After stirring the mixture for 30 minutes, 1.5 ml of pyridinewere added and the reaction mixture stood overnight at room temperature.The mixture was then filtered and the filtrate was evaporated to drynessunder reduced pressure at 30C. The residue was taken up in 30 ml ofether, filtered and concentrated to dryness. The residue waschromatographed over silica gel and eluted with methylene chloride andcrystallized from methanol to obtain 151 mg of the cis form, 77 mg ofthe trans form and 167 mg of a mixture of the cis and trans form of thebenzyl ester of DL 7-tritylamino-desacetoxycephalosporanic acid. The cisform of the said ester melted at 184C and occurred as colorless crystalssolu ble in chloroform, slightly soluble in methanol, ethanol and etherand insoluble in water. The trans form melted at 200C.

Analysis of cis: C H O N S; molecular weight 546.69: Calculated: %C74.71; %H 5.53; %N 5.13; %S 5.85; Found: C 74.5; H 5.5; N 5.0; S 5.4U.V. Spectrum (ethanol):

ClS

Inflex. towards 227 nm: E lnflex. towards 259 nm: E Max. at 262 nm: E111 lnflex. towards 267 nm: E 106 Trans lnflex. towards 228 nm: E 293lnflex. towards 256 nm: E 126 EXAMPLE IV TERT BUTYL ESTER OF CIS DL7-AMINO-DESACETOXY-CEPHALOSPORANIC ACID A current of gaseous hydrogehchloride was passed through a solution of 0.5 g of the tert-butyl esterof cis DL 7-tritylamino-desacetoxy-cephalosporanic acid in 5 ml ofchloroform for 3 minutes at room temperature and the chloroform wasremoved under reduced pressure. The residue was taken up in ether toobtain 0.280 g of the hydrochloride of the tert.butyl ester of cis DL-7-amino-desacetoxy-cephalosporanic acid. The said hydrochloride wasdissolved in a mixture of 0.5 ml of methanol and 1.5 ml of water and themixture was vac uum filtered and the filter was rinsed with a littlemethanol. The filtrate was made alkaline by the additon of 6 drops oftriethylamine and was then iced and vacuum filtered. The precipitate waswashed with water and dried to obtain 0.222 g of the tert.-butyl esterof cis DL 7-amino-desacetoxycephalosporanic acid melting at C. Theproduct occurred in the form of colorless crystals soluble inchloroform, slightly soluble in methanol and insoluble in water.

Analysis: c gH gogNgs; molecular weight 270.34; Calculated: %C 53.22; %H6.71; %N 10.37; %S 11.86; Found: C 53.1; H 6.8; N 10.7; S 12.0 IRSpectrum (chloroform):

Presence of NH at 3401 and 3333"', of Blactam at 1775"", of conjugatedester at 1718 and of C=C and NH deformation at 1640 and 1625""" U.V.Spectrum (ethanol):

Max. at 219 nm: E

lnflex. towards 261 nm: E 220 Max. at 271 nm: E 234; e 6300 EXAMPLE VUsing the procedure of Example IV, the corresponding ethyl ester of cisand trans DL 7-amino-desacetoxycephalosporanic acid were prepared bydetritylation of the ethylester of the respective cis and trans DL 7-tritylamino-desacetoxycephalosporanic acid.

EXAMPLE VI Using the procedure of Example IV, the benzyl ester of cisand trans DL 7-amino-desacetoxy-cephalosporanic acid were prepared bydetritylation of the benzyl ester of the respective cis and trans DL7-tritylaminodesacetoxy-cephalosporanic acid.

EXAMPLE Vll TERT.-BUTYL ESTER OF ClS L7-AMlNO-DESACETOXY-CEPHALOSPORANIC ACID 7.2 g of the tert.-butyl esterof cis DL 7- aminodesacetoxy-cephalosporanic acid were added to asolution of 4.39 g of D tartaric acid in 45 ml of methanol and themixture was refluxed. The mixture was cooled and held a few minutes at20C and was then vacuum filtered. The precipitate was washed withmethanol, then ether and dried to obtain the tartrate of the said acid.The tartrate was suspended in 46 ml of methanol and after the additionof 3.3 ml of triethylamine, the mixture was stirred for 5 minutes andfiltered to remove insolubles. The filtrate was added to water and themixture was extracted with methylene chloride. The organic phase wasdried over magnesium sulfate and the solvent was evaporated underreduced pressure. The residue was crystallized from petroleum ether toobtain 2.73 g of the tert.butyl ester of cis L 7-amino-desacetoxy-cephalosporanic acid melting at 126C and having aspecific rotation of [01],, +100 t 3 (C=O.5% in chloroform).

' The tert.-butyl ester of cis D 7-aminodesacetoxycephalosporanic acidwas obtained from the methanolic mother liquors and the said ester had amelting point of 126C and a specific rotation [01],, lO0 3 (C=0.5% inchloroform).

Various modifications of the process and products of the invention maybe made without departing from the spirit or scope thereof and it is tobe understood that the invention is to be limited only as defined in theappended claims.

We claim:

I. A process for the preparation of a compound of the formula in theform of cis, trans or cis-trans mixtures wherein R is selected from thegroup consisting of hydrogen and trityl and R is lower alkyl of l to 6carbon atoms optionally substituted with a chlorine and phenylalkyl of 7to 15 carbon atoms comprising the steps of reacting an enamine of theformula lll cooR H which occurs in erythro and/or threo isomeric form,reacting the latter in the presence of a tertiary amine with an ester ofa-keto-B-methylene-butyric acid of the formula wherein R has the abovedefinition to form a 1,3- thiazane of the formula CooRn NH CHCH:;

HO COOR;

in the form of its erythro and/or threo form independent of theconfiguration of 3- and 4-carbon atoms, reacting the latter with an aciddehydrating agent to form a 1,3-thiazine of the formula COORn NH CH Vlloccurring in the form of its erythro and/or threo isomers, subjectingthe latter to reaction with hydrazine for a functional exchange to forma compound of the formula 23 occurring in the form its erythro and/orthreo isomers, selectively saponifying the latter with a dilute aqueousalkali metal base to form a compound of the formula COOH NH C-CH;

COOR

occurring in the form of its erythro and/or threo isomers, reacting thelatter with trityl chloride to form a compound of the formula in theform of cis, trans or cis-trans mixtures, wherein R is selected from thegroup consisting of hydrogen and trityl and R is selected from the groupconsisting of alkyl of l to 6 carbon atoms optionally substituted with achlorine and phenylalkyl of 7 to carbon atoms comprising the steps ofreacting an enarnine of the formula wherein Y is selected from the groupconsisting of cyclic imido, benzoylamino and thiobenzoylamino and R isselected from the group consisting of alkyl of l to lo carbon atoms andphenylalkyl of 7 to 15 carbon atoms with hydrogen sulfide in thepresence of an acid HX wherein X is selected from the group consistingof chlorine, bromine, -SO H and SO H to obtain a thioaminal of theformula in the form of its erythro and/or threo isomers, condensing thelatter in the presence of a tertiary amine with an ester of the formulato form a 1,3-thiazane of the formula YCH H cH cooR,,NH cH cH c HO/cooR,

in the form its erythro and/or threo isomers independent of the 3- and4- carbon atoms configuration, treating the said product with an aciddehydrating agent to form a compound of the formula YCH H H cooR,,NH\/c-cH cooR in the form of its erythro and/or threo isomers, subjectingthe latter to functional exchange with hydrazine to form a compound ofthe formula in the form of its threo and/or erythro isomers, reactingthe latter with an acid of the formula l-lX wherein X is selected fromthe group consisting of chlorine, bromine and an acyl of an organic acidto obtain the acid addition salt of the formula cooR in the form of itserythro and/or threo isomers, reacting in the form of its erythro and/orthreo isomers, conthe latter with a dilute aqueous alkali metal base toobdensing the latter in the presence of a tertiary amine tain a compoundof the formula ith an ester of the formula n H N CHCH (H g c H coon Mi//CCH;, CIOOR2 600R: to form a 1,3-thiazane of the formula in the formof its threo and/or erythro isomers, reacting the latter with tritylchloride to obtain a compound of the formula YCHCH H OOR NI CH--CH C(CGH5);;CNHCH(|IH (11 HO C0011 NH C CH" in the form its erythro and/orthreo isomers independent of the 3- and 4-carbon atoms configuration,treating the said product with an acid dehydrating agent to COOR2 form acompound of the formula in the form of its erythro and/or threo isomersand cyclizing the latter with a dialkylcarbodiimide ordicycloalkylcarbodiimide lactamization agent to obtain CH2 the desired7-tritylammo cephalosporamc acid com- A OOR NH CCH pound. \J

4. A process for the preparation of DL 7aminodesacetoxy-cephalosporanicacid compounds of the (300R2 formula in the form of its erythro and/orthreo isomers, subjecting the latter to functional exchange withhydrazine to form a compound of the formula R-NHCtH?H (IIH (-N C S c cu, H;N H-CH CH COOR a i 3 in the form of C15, trans or cis-transmixtures, wherein COORZ R is selected from the group consisting ofhydrogen and trityl and R is selected from the group consisting of inthe form of its threo and/or erythro isomers, selecalkyl of l to 6carbon atoms optionally substituted with tively saponifying the latterwith a dilute aqueous alkali a chlorine and phenylalkyl of 7 to 15carbon atoms metal baseto form a l,3 thiazine of the formula comprisingthe steps of reacting an enamine of the formula /S\ H NCH--CH (lJH COOHNH c cH COOR wherein Y is selected from the group consisting of cyc-(300Rz lic imido, benzoylamino and thiobenzoylamino and R is selectedfrom the group consisting of alkyl of l to 10 in the form of its erythroand/or threo isomers, reacting carbon atoms and phenylalkyl of 7 to 15carbon atoms the latter with trityl chloride to form a compound of thewith hydrogen sulfide in the presence of an acid HX formula wherein X isselected from the group consisting of chlo- ,0 ride, bromine, SO H andSO H to obtain a thil COOR cooR in the form of its erythro and/or threoisomers, reacting carbodiimide or dicycloalkylcarbodiimide lactamizathelatter with a secondary amine to form the corretion agent to form thedesired 7-tritylamino-cephalossponding amine salt, hydrolyzing the saidsalt under poranic compound. acid conditions followed by cyclizationwith a dialkyl- UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 5,9OOyLt68 Dated August 9, 1975 Inventor) Jacques Martel andRene Heymes g 1 O 9 It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Col. Page Line Line [57] I Formula H "RNH-%. CH CH t 2 I .'N C-CH l 6 QCOOR should be H Q S l --R NH-(IL (12H l I C I\[ C-CH a f OOR UNITEDSTATES PA'IEN'I OFFiCE Page 2 of 9 QERHFICA'IE 0F CORREC'HON Patent No.3; 9 L168 Dated Aug 9 975 Inventor s QUES MARTEL AND RENE. HEYMES It iscertified that error appears in the aboveidentified patent and that saidLetters Patent are hereby corrected as shown below:

Col. Line Page Line NH G) 2 1o 3 1M "YCH CH\ X should be SH COOR IV ,NH3G) Y CH CH/ X 9 IV COOR3 SH 3 f n u 3 0O 6 9 (0 1 1 0 NH (3H2 X' H2N CH3I COOR2 should be s --(C6H5)3 C-NHCH (EH2 coo NH 0 1 i i 2 UNITED STATESPATENT OFFICE Page 3 of 9 CERTIFICATE OF CORRECTION Patent No. ,9 l68Dated g- 9, 975

Inventor(s) JACQUES MARTEL AND RENE HEYMES It is certified that errorappears in the above-identified patent: and that: said Letters Patentare hereby corrected as shown below:

Col. Line Page Line A 2 6 11 "H should be --H N 5 50 9 19 H l H h \f sould be Q VI should be UNTTED STATES PATENT OFFICE P u f 9 age 0CERTIFICATE OF CORRECTION Patent No. ,568 Dated Aug. 19, 1975Inventor(s) JACQUES MARTEL AND RENE HEYMES It is certified that errorappears in the above-identified patentand that said Letters Patent arehereby corrected as shown below:

Col Line Page Line 6 25 l0 l5 "Yuc S should be I H XI Y COOR l 3 COOR-Y'CH XI COOR EH D COOR " C H C-HN- X D COQH CH COOR should be UNITEDSTATES PATENT OFFICE CERTIFICATE OF CORRECTION of 9 Patent No. 3300, 168Dated Aug. 19, 1975 JACQUES MARIEL AND RENE HEYMES Inventor(s) It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Col. Line Page Line 6 60 ll 16 (Cont'd) c H c-HN-T 3 COOR3 9 26 16 1"Max at 290 290" should be -Max at 290 run-- "ll7;" should be -ll7- 9 23"969;" should be --96 l-- 9 41 16 1 1 "reisdue" should be --r'esidue-- 917 2 should be --l20- 12 11 23 3 "=6,000 should be -e 6,000-- 12 5O 2318 "thiazane" should be -thiazine-

1. A PROCESS FOR THE PREPERATION OF A COMPOUND OF THE FORMULA
 2. Theprocess of claim 1 wherein the trityl derivative is subjected to acidhydrolysis to obtain the corresponding 7-amino compound.
 3. A processfor the preparation of DL 7-amino-desacetoxy-cephalosporanic acidcompounds of the formula
 4. A process for the preparation of DL7-amino-desacetoxy-cephalosporanic acid compounds of the formula